Bonding agents are one of the most important components of solid propellants that enhance the interaction between solid particles and binders. Many bonding agents have been reported so far and sufficient laboratory studies have been carried out on their mechanism of action, including, hydantoin, isocyanorathe, vinyl ether, base-shif, etc. Borate esters are other group of bonding agents that mostly have successful results in four-component solid propellants and improve the mechanical properties of the propellants. In this paper, while introducing borate esters as a bonding agent, the study of Borate ester preparation methods, Borate ester application in the four-component HTPB, the effect of borate ester bonding agent on mechanical properties of the propellant containing RDX, the effect of increasing the amount of BEBA on Mechanical properties of the propellants, comparison of mechanical properties of the propellants produced by BEBA and MAPO, the processor of propellants using propellants containing BEBA and the effects of various bonding agents, such as borate esters, on the propellant ballistic properties.